High-frequency phase shifters are used in antenna engineering for changing the phase position of a signal with which the radiators of an antenna array are supplied. High-frequency phase shifters in particular serve for the electrical tilt of the radiation pattern.
High-frequency phase shifters typically have a rotatably supported pick-up element which is electrically coupled to a feed line via a coupling point arranged in the region of its rotary axle. The pick-up element contacts a stripline section at different positions depending on its rotary position. The signal path and thus the phase position are hereby varied depending on the rotary position of the pick-up element, the pick-up element can in particular be configured in pointer form and can optionally contact a plurality of stripline sections which are arranged at different distances from the rotary axle of the pick-up element. A high-frequency phase shifter can hereby control a plurality of radiators each having different phase shifts. Such a high-frequency phase shifter is known, for example, from EP 1 208 614 B1.
It is, however, frequently necessary with larger antenna arrays to use a plurality of separate high-frequency phase shifters which are, however, synchronously adjusted. To achieve a particularly compact arrangement of the high-frequency phase shifters, they can be arranged stacked above one another. To shield the high-frequency phase shifter toward the outside, they are typically arranged in a housing. To adjust the pick-up elements of the high-frequency phase shifters synchronously, they are mechanically coupled to one another by a common rotary axle in the stack with known high-frequency phase shifter assemblies. The pick-up elements hereby rotate synchronously on a rotation of the common rotary axle.
In prior art high-frequency stacked phase shifter assemblies, a housing plate having an axial passage in the region of the rotary axle, is typically provided in the stack between the high-frequency phase shifters for the electrical decoupling of the high-frequency phase shifters. The shielding of the high-frequency phase shifters between one another is, however, hereby degraded just where the signal is fed from the feed lines into the pick-up elements. This has negative effects on the electrical decoupling of the high-frequency phase shifters. The distance between the two phase shifters and the diameter of the axial passage as well as the material of the axial passage are decisive for the decoupling of the two phase shifters, with it having partly been necessary in the prior art to increase the spacing of the phase shifters in the stack to achieve a sufficient decoupling. Due to the restrictions of construction space and to the mechanical demands on the common rotary axle, the decoupling of the high-frequency phase shifters in the stack can therefore not be improved as desired.
It is therefore the object of the present disclosure to further develop a high-frequency phase shifter assembly having at least two phase shifters stacked above one another such that the decoupling of the high-frequency phase shifters in the stack is improved.
This object is achieved in accordance with the present disclosure by a high-frequency phase shifter assembly having at least two high-frequency phase shifters, and by a stackable high-frequency phase shifter.
Advantageous embodiments of the present disclosure form the subject of the dependent claims.
The present disclosure comprises a high-frequency phase shifter assembly having at least two high-frequency phase shifters which are stacked above one another and which are arranged in at least one housing, wherein at least one housing plate is provided between the high-frequency phase shifters in the stack. The high-frequency phase shifters each have a rotatably supported pick-up element which is electrically coupled to a feed line via a coupling point arranged in the region of its axis of rotation. The pick-up elements of the high-frequency phase shifters are mechanically coupled for the synchronous adjustment of the high-frequency phase shifters. Provision is made in accordance with the present disclosure that the mechanical coupling of the pick-up elements of the high-frequency phase shifters takes place via a coupling arrangement spaced apart from the rotary axles of the pick-up elements.
The mechanical coupling thus no longer takes place in accordance with the present disclosure by a common rotary axle of the frequency phase shifters, but rather via a coupling arrangement spatially separate from the rotary axles. This allows the rotary axles of the individual pick-up elements to be completely separated from one another and also to allow an improved shielding by the housing plate arranged between the high-frequency phase shifters in the region of the rotary axles.
Since no continuous rotary axles of the pick-up elements is provided at the stack, but the mechanical coupling rather takes place spaced apart from the rotary axles, an improved decoupling is possible in accordance with the present disclosure. The high-frequency phase shifters may have an electrical decoupling of at least 25 dB, optionally of at least 29 dB, further optionally of at least 35 dB, and further optionally of at least 40 dB.
In accordance with the present disclosure, the spacing of the phase shifters in the stack can be reduced in accordance with the present disclosure since it is no longer as decisive in the same way for the decoupling as in accordance with the prior art, the spacing of the phase shifters in the stack can be less than 17 mm, optionally less than 15 mm, and further optionally less than 12 mm.
Since a continuous rotary axle of the pick-up elements is no longer provided, the housing plate arranged between the high-frequency phase shifters in the stack in the region of the rotary axle no longer has to have a passage opening for the rotary axle so that this region of the housing plate can be improved with respect to its decoupling properties, apertures, for example in the form of inspection openings, can by all means still be provided in the region of the rotary axles. They can, however, be smaller than the axial passages required in the prior art.
The at least one housing plate arranged in the stack between the high-frequency phase shifters may have no apertures in the region of the rotary axles of the pick-up elements whose outer circumference is greater than ⅛ of the minimal wavelength of the signals at which the high-frequency phase shifter assembly is operated. The housing plate optionally has no apertures in the region of the rotary axles of the pick-up elements whose outer circumference is greater than 1/10, and optionally greater than 1/15, of the minimal wavelength of the signals. The outer circumference is of particular importance for the electrical decoupling due to induced circulating current about the margins of the opening.
The housing plate therefore may have no apertures relevant for the electrical decoupling in the region of the rotary axles. The apertures should in particular also not relevantly impair the shielding for the minimal wavelength of the signals at which the high-frequency phase shifter assembly is operated. In a possible embodiment, the housing plate has no apertures at all in the region of the rotary axles.
With the high-frequency phase shifter assemblies in accordance with the present disclosure, the high-frequency phase shifters can be stacked above one another such that the rotary axles of the respective pick-up elements extend in parallel with one another and are optionally aligned with one another. This allows a particularly compact arrangement. The coupling points arranged in the region of the rotary axles for the decoupling of the signals into the pick-up elements are also electrically decoupled from one another with such an aligned arrangement of the rotary axles since the housing plate disposed therebetween prevents an electrical coupling.
The pick-up elements of the high-frequency phase shifters are configured in pointer shape in a preferred embodiment and have one or more coupling points with which they are electrically coupled to one or more stripline sections. The ends of the stripline sections can be connected to radiators so that the wavelength of the signals to the radiators and thus the phase position is shifted by a rotation of the pick-up element, the one or more stripline sections may extend concentrically about the rotary axle of the pick-up element. If a plurality of stripline sections are provided, they typically have a different radial spacing from the rotary axle so that the adjustment of the pick-up element results in different phase shifts for the individual stripline sections. The pick-up element itself can likewise be configured as a rotatable stripline section of pointer shape, wherein, with a plurality of stripline sections, the coupling points of the pick-up element to the stripline sections are arranged following one another at the stripline section of pointer shape forming the pick-up element.
The coupling between the feed line and the pick-up element may take place capacitively in the region of the coupling point, the pick-up element can in particular have a ring-shaped line section in the region of the rotary axle, said ring-shaped line section being separated by a dielectric from a line section likewise of ring shape and connected to the feed line. The coupling between the pick-up element and the stripline sections optionally also takes place capacitively.
The individual high-frequency phase shifters in the stack can be configured such as is known from EP 1 208 614 B1.
The high-frequency phase shifter assembly in accordance with the present disclosure can in a first embodiment have a common housing in which at least two high-frequency phase shifters are arranged stacked above one another. In this case, the at least two high-frequency phase shifters are separated from one another by an intermediate plate of the housing. If more than two high-frequency phase shifters are provided, a respective at least one intermediate plate is provided between the individual high-frequency phase shifters.
In an alternative embodiment, the high-frequency phase shifters can each have their own housing, with the housings of the high-frequency phase shifters being stacked on one another and being connected to one another for forming the high-frequency phase shifter assembly. This allows the flexible provision of high-frequency phase shifter assemblies having different numbers of high-frequency phase shifters since a corresponding number of high-frequency phase shifters which each have their own housings are stacked on one another in dependence on the requirement. The housings of the individual high-frequency phase shifters do not have any axial passage at least on one side in the region of the rotary axle of the pick-up element and thus likewise allows a good electrical decoupling of the individual high-frequency phase shifters in the stack.
The individual high-frequency phase shifters can be arranged at a smaller spacing from one another in the stack due to the improved decoupling achieved by the lacking continuous rotary axle, the spacing between the housings of high-frequency phase shifters following one another in the stack can be less than 11 mm, optionally less than 8 mm, further optionally less than 5 mm, and further optionally less than 2 mm. Provision can furthermore be made that the housings of the high-frequency phase shifters in the stack lie on one another, optionally with the interposition of an insulating layer. The construction height is hereby reduced.
Independently of a common housing for the high-frequency phase shifter assembly or of respective separate housings for the high-frequency phase shifters, the housing or housings may be configured as closed housings. Such a closed housing may have a base plate and a top plate which may extend perpendicular to the rotary axle of the pick-up element and has side walls which extend between the base plate and the top plate and close the housing. However, certain openings can naturally be provided in the individual plates or walls. The openings, however, may have less than 20% of the surface of the housing, further optionally less than 10%. In a possible embodiment, the side walls can be formed as angled sections of a metal sheet forming the top plate and can be connected via fastening lugs, for example, to a metal sheet forming the base plate. The housing may be formed from metal or have a metallic coating. For example, instead of a metal housing, a plastic housing having a metallic surface can be used, in particular a housing of electroplated plastic.
The specific design of the coupling arrangement via which the mechanical coupling of the pick-up elements of the individual high-frequency phase shifters takes place in the stack can initially be in accordance with the present disclosure. What is solely decisive here is that the mechanical coupling does not take place by a common rotary axle of the pick-up elements, but rather by a coupling arrangement spaced apart from the rotary axles to allow the separation of the rotary axles by the housing plate.
The coupling arrangement can be arranged wholly or partly outside the housing or housings in a possible embodiment. In this case, the rotary axle of the pick-up elements may be led out of the housing at one side and is connected to the coupling arrangement there. The rotary axle is in contrast not led out of the housing at the other side, but is rather at least partly separated from the next rotary axle by a housing plate.
The coupling arrangement can in an alternative embodiment be arranged wholly or partly inside the housing or housings. In this case, the rotary axle of the pick-up elements is not led out of the housing at all, but is rather connected to the coupling arrangement inside the housing. The rotary axle of one or more pick-up elements can, however, optionally also be led out of the housing at one side with a coupling arrangement arranged inside the housing and can serve as a drive axle for the high-frequency phase shifter assembly.
Possible embodiments for mechanical coupling arrangements in accordance with the present disclosure will be shown in more detail in the following:
In a first possible embodiment, the mechanical coupling of the pick-up elements of the high-frequency phase shifters takes place by a gearing. The gearing may have at least one connection shaft extending offset from the rotary axles of the pick-up elements. The connection shaft may extend in parallel with the rotary axles, but at a certain spacing from them.
In this respect, respective first gearing elements may be rotationally fixedly connected to the pick-up elements and cooperate with second gearing elements which are arranged at the connection shaft to transmit a rotational movement between the connection shaft and the pick-up elements. The gearing elements can in particular be gear wheels or geared segments. The first and second gearing elements can be arranged such that they directly mesh with one another. Optionally, however, further gearing elements can also be interposed between the first and second gearing elements.
The second gearing elements are coupled with one another by the connection shaft in accordance with the present disclosure and thus allow a mechanical coupling of the pick-up elements without the rotary axles of the pick-up elements being directly coupled to one another. For unlike in the prior art, the pick-up elements thus do not have a common rotary axle, but rather the second gearing elements spaced apart from the rotary axle.
The gearing which is used for the mechanical coupling of the individual pick-up elements of the high-frequency phase shifters can be arranged in a possible embodiment completely outside the housing of the high-frequency phase shifter assembly or outside the housings of the individual high-frequency phase shifters. For this purpose, the rotary axle of the pick-up elements can respectively be led out of the housing at one side and can be rotationally fixedly connected to the first gearing element there. The first gearing elements, the second gearing elements and the connection shaft can thus be arranged outside the respective housings. The gearing, however, may be at least partly arranged within the housing of the high-frequency phase shifter assembly or of the respective housings of the high-frequency phase shifters, at least the first and second gearing elements can in particular be arranged within the housing or housings.
The connection shaft is optionally led via an axial passage through the at least one housing plate arranged between the high-frequency phase shifters. An aperture admittedly has to be provided for the connection shaft of the second gearing elements in the housing plate which separates the high-frequency phase shifters in the stack. This is, however, no longer arranged in the region of the rotary axle of the pick-up element and of the coupling point for the electrical coupling of the pick-up element in accordance with the present disclosure, but rather remote herefrom so that the axial aperture has no negative influence on the decoupling of the high-frequency phase shifters. The connection shaft may be arranged on a side disposed opposite the stripline sections with respect to the rotary axle of the pick-up element.
In a possible embodiment, the high-frequency phase shifter assembly has a common housing, with the connection shaft also extending within the housing. The coupling arrangement may thus be located completely within the housing.
To be able to actuate the high-frequency phase shifter assembly or to be able to adjust the pick-up elements synchronously, the connection shaft or at least one of the rotary axles of the pick-up elements or a further drive shaft can be led out of the housing.
In accordance with a further, preferred embodiment of the present disclosure, the high-frequency phase shifters each have their own housings, with the housings being stacked on one another and connected to one another to form the high-frequency phase shifter assembly, a respective gearing element is arranged within the housing of a high-frequency phase shifter; it is rotationally fixedly connected to the pick-up and cooperates with a second gearing element likewise arranged in the housing of the high-frequency phase shifter. The first and second gearing elements may be rotatably supported in or at the housing. The first gearing element can in particular be rotatably supported together with the pick-up element. The second gearing elements can in particular be arranged offset next to the first gearing element and optionally mesh with them. The rotary axles of the first and second gearing elements optionally extend in parallel with this respect.
The second gearing elements arranged in the respective housings can be coupled to one another in accordance with the present disclosure. The second gearing elements of the high-frequency phase shifters stacked above one another may be connected to one another via a connection shaft led in the respective housings through axial passages.
In a first possible embodiment, the second gearing elements can be connected to one another by a continuous connection shaft passing through shaft openings in the second gearing elements. The desired number of high-frequency phase shifters can hereby be stacked on one another and the second gearing elements can then be connected in a mechanically coupled manner by pushing the connection shaft through the shaft openings of the second gearing elements.
In an alternative embodiment, the second gearing elements can each have connection shaft sections which are connected to a connection shaft section of a second gearing element of a high-frequency phase shifter arranged below or above it. This also allows a simple stacking of any desired number of high-frequency phase shifters. The connection shaft sections can optionally be connectable to one another via a plug-in connection and/or releasably.
The housing of the high-frequency phase shifters may have apertures for the connection shaft at both sides of the rotary axle of the second gearing elements.
In accordance with the present disclosure, a plurality of high-frequency phase shifters of identical design at least with respect to the housing and to the connection of the second gearing elements can be put together to form a high-frequency phase shifter assembly in accordance with the present disclosure. The housings of the individual high-frequency phase shifters can have connection points, for example in their base plate, via which the individual high-frequency phase shifters arranged in the stack can be connected to one another, for example, by the passing through of connection elements.
In a possible embodiment of the present disclosure, the gear ratio of the gearing can the same for each high-frequency phase shifter of the high-frequency phase shifter assembly so that an identical adjustment of the high-frequency phase shifters results on a movement of the gearing.
In an alternative embodiment, the gearing for the respective high-frequency phase shifter can, however, also have different gear ratios so that a respective different adjustment of the individual high-frequency phase shifters results on a movement of the gearing. The high-frequency phase shifters in the stack are admittedly still moved synchronously, but with different adjustment angles so that different phase shifts accordingly result.
As just described, a gearing can thus be used as a mechanical coupling arrangement for coupling the pick-up elements of the high-frequency phase shifters in the stack. The present disclosure is, however, not limited to this embodiment.
In an alternative embodiment, the mechanical coupling of the pick-up elements of the high-frequency phase shifters can in contrast take place via a lever arrangement. The levers may be respectively rotationally fixedly connected to the pick-up elements and extend away from the rotary axle of the pick-up elements so that they can be coupled to one another in a region which is spaced apart from the rotary axle. An arrangement of rods can be provided for moving the levers. The coupling of the levers of the individual high-frequency phase shifters can either take place indirectly via the arrangement of rods or directly, for example, via a connection rod.
The coupling between the linkage and the levers may take place via one or more slotted guides in which one or more entrainer pins are guided. A displacement of the arrangement of rods in a direction tangential to the rotary axle of the pick-up element hereby results in a rotational movement of the lever and of the pick-up element, with the guide pin moving along in the slotted guide. The slotted guide may be formed as an elongate hole. In a possible embodiment, the guide pin is arranged at the lever and is guided in a slotted guide arranged at the arrangement of levers.
In a first possible embodiment, the levers of the individual high-frequency phase shifters can have the same length or be connected to the arrangement of rods in the same manner so that an identical adjustment of the high-frequency phase shifters results on a movement of the arrangement of rods. If the coupling of the levers to the arrangement of rods takes place respectively separately via a separate slotted guide, the guide pins associated with the individual levers may have the same spacing from the rotary axle of the lever and thus from the pick-up element so that the same lever arm respectively results. It is alternatively conceivable to connect the individual levers directly and rigidly to one another so that only one guide pin and one slotted guide can be used to adjust a plurality of levers and thus a plurality of high-frequency phase shifters.
In an alternative embodiment, the levers of the individual high-frequency phase shifters can have different lengths and/or can be connected separately to the arrangement of rods so that different adjustments of the individual high-frequency phase shifters result on a movement of the arrangement of rods. The entrainer pins associated with the individual levers may have different spacings from the rotary axle of the levers or of the pick-up elements so that different lever arms result. On a linear adjustment of the arrangement of rods, a respective different rotational movement of the levers and thus of the pick-up elements hereby results. The pick-up elements admittedly hereby continue to be adjusted, but generate different phase shifts.
The levers associated with the respective pick-up elements may extend in a plane which is perpendicular to the rotary axle of the pick-up element. The levers may extend radially to the rotary axle of the pick-up element.
In a first possible embodiment, the levers can each be led out the housing through a slit therein on the side of the rotary axle disposed opposite the pick-up element. A small construction height hereby results.
Such an arrangement is conceivable, on the one hand, when all high-frequency phase shifters in the stack have a common housing. In this case, the common housing has a corresponding number of slits in a corresponding side wall through which slits the levers are led to the outside.
Such an embodiment is, however, also conceivable when the individual high-frequency phase shifters each have their own housings. In this case, the housing of each high-frequency phase shifter has a corresponding slit through which the lever is led to the outside.
In an alternative embodiment, the rotary axles of the pick-up elements can, however, each be led out of the housing on one side and the levers can be connected to the rotary axle outside the housing. In contrast, a housing plate which separates the individual rotary axles from one another is provided at the oppositely disposed side of the rotary axles.
In an arrangement with only two phase shifters stacked above one another, the rotary axle of the pick-up element in the upper high-frequency phase shifter can be led out of the housing to the top and can be led out of the housing to the bottom in the lower one.
An arrangement is alternatively conceivable in which every high-frequency phase shifter has its own housing, with the rotary axles in each case being led out of the housing at the same side. In this case, the lever extends at least in the interior of the stack between the top plate of the housing of a phase shifter and a base plate of another phase shifter.
In addition to the above-described high-frequency phase shifter assemblies having a plurality of high-frequency phase shifters stacked on one another, the present disclosure furthermore comprises stackable high-frequency phase shifters for providing such high-frequency phase shifter assemblies.
Such a stackable high-frequency phase shifter has its own housing in which a rotatably supported pick-up element is arranged which is electrically coupled to a feed line via a coupling point arranged in the region of its rotary axle. The high-frequency phase shifter has a coupling element which allows a coupling, remote from the rotary axle of the pick-up element, of the movement of the pick-up element of the high-frequency phase shifter with the movement of a pick-up element of another high-frequency phase shifter. A high-frequency phase shifter assembly in accordance with the present disclosure can be provided by stacking one or more such high-frequency phase shifters on one another, such as was described above.
The stackable high-frequency phase shifter can be configured such as has already been described in more detail above with respect to the high-frequency phase shifter assembly.
The coupling point can in particular be electrically shielded to the outside by the housing at least toward one side of the rotary axle. Two high-frequency phase shifters stacked above one another can furthermore have an electrical decoupling of at least 25 dB, further optionally of at least 29 dB, further optionally of at least 35 dB, and further optionally of at least 40 dB.
Provision can furthermore be made that the housing in the region of the rotary axle of the pick-up element at least has no apertures toward one side of the rotary axle whose outer circumference is greater than ⅛ of the minimal wavelength of the signals at which the high-frequency phase shifter is operated. The housing may have at least has no apertures in the region of the rotary axle of the pick-up element toward one side of the rotary axle whose outer circumference is larger than 1/10 and is further optionally larger than 1/15 of the minimal wavelength of the signals.
The housing in a possible embodiment can have a thickness in the stack direction of less than 17 mm, optionally less than 15 mm, further optionally of less than 12 mm.
A first gearing element can furthermore be arranged within the housing and is rotatably fixedly connected to the pick-up element and cooperates with a second gearing element likewise arranged in the housing. The second gearing element may allow a mechanical coupling with other high-frequency phase shifters in the stack.
The housing in particular has an axial passage for a connection shaft at both sides in the region of the second gearing element. The second gearing elements of the individual high-frequency phase shifters and thus their pick-up elements can be mechanically coupled to one another for this connection shaft without the rotary axles of the pick-up elements having to be directly connected to one another.
In a possible embodiment, the second gearing element has a shaft opening through which the connection shaft can be pushed. Alternatively, the second gearing element can have a connection shaft section which is connectable to a connection shaft section of a high-frequency phase shifter arranged thereabove or thereunder. The connection shaft sections may be connectable to one another via a plug-in connection and/or releasably.
Alternatively to the gearing, the high-frequency phase shifter can also have a lever via which the pick-up element is movable. The lever is rotationally fixedly connected to the rotary axle of the pick-up element for this purpose.
In a first possible embodiment, the lever can be connected to the pick-up element in the housing and can be led out of the housing through a slit on the side of the rotary axle disposed opposite the pick-up element.
Alternatively, the rotary axle of the pick-up element can be led out of the housing on one side and the lever can be connected to the rotary axle outside the housing.
The housing of a stackable high-frequency phase shifter in accordance with the present disclosure can, for example, comprise a base plate, a top plate and side walls. The top plate and the side walls can be shaped by a contiguous, correspondingly bent metal plate. The base plate can have connection points which allow a connection of the individual high-frequency phase shifters in the stack, connection openings can in particular be provided through which connection elements pass which connect the individual high-frequency phase shifters to one another.
The high-frequency phase shifter in accordance with the present disclosure may be configured such that it is stackable with further high-frequency phase shifters which are at least of identical design with respect to the housing, in particular such that the rotary axles of the pick-up elements are arranged in parallel with one another and may be aligned with one another. If the mechanical coupling takes place via second gearing elements such as have already been described above, their rotary axles are optionally also aligned.
The present disclosure furthermore comprises a high-frequency antenna having a high-frequency phase shifter assembly such as has been described above and having a plurality of radiators which are controllable via the high-frequency phase shifter assembly. The radiators may be connected to the high-frequency phase shifters of the high-frequency phase shifter assembly in accordance with the present disclosure such that the radiation pattern of the antenna can be electrically oriented and in particular reduced by an adjustment of the high-frequency phase shifter assembly. It can in particular be a cellular radio antenna.
The high-frequency phase shifter assembly in accordance with the present disclosure can be able to be manually actuated in a first embodiment. For example, an adjustment element, e.g. a rotary knob, can be provided via which the high-frequency phase shifters can be adjusted. Alternatively or additionally, the high-frequency phase shifter assembly can also be adjustable by a motor. A corresponding drive motor may be provided for this purpose.
In the first embodiment, in which a gearing is used as a mechanical coupling element, the adjustment element or the drive motor can be connected to the connection shaft, to a rotary axle of a pick-up element or to an additional drive axis. In the second embodiment, in which a lever arrangement is used as the coupling arrangement, the adjustment element or the drive motor may move an arrangement of rods coupled to the levers.
The present disclosure will now be represented in more detail with reference to embodiments and to drawings.